Electronic properties of several two dimensional halides from ab initio calculations

• Mohamed Barhoumi,
• Ali Abboud,
• Lamjed Debbichi,
• Moncef Said,
• Torbjörn Björkman,
• Dario Rocca and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2019, 10, 823–832, doi:10.3762/bjnano.10.82

• electronic structure is important for the fabrication of transistors. Therefore, we have used a similar strategy to tune the bandgap of the different monolayers, with electric fields up to 1.0 V/Å applied perpendicularly. A full relaxation of the structure was conducted under the electric field. Notice that

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• are detailed here as resulted from DFT calculations. Van der Waals interactions as well as the strong correlation in 3d orbitals of transition metals were taken into account in all calculations, including the structural relaxation. For each system we investigate four relative positions of the metallic

• structures and relaxation procedure for molecule are presented in the next section. The exchange–correlation (xc) functionals used in DFT are plagued by one- and many-electron self-interaction error (SIE) [59]. In the case of correlated electrons this effect may lead to significant errors. One of the most

• atoms. Further relaxation of the positions of nitrogen atoms will probably diminish these values, which should be considered as the maximum possible values. It is interesting to observe that the dependence on the adsorption position is weaker from left to right in the panels of Figure 1, suggesting that

Outstanding chain-extension effect and high UV resistance of polybutylene succinate containing amino-acid-modified layered double hydroxides

• Adam A. Marek,
• Vincent Verney,
• Christine Taviot-Gueho,
• Grazia Totaro,
• Laura Sisti,
• Annamaria Celli and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2019, 10, 684–695, doi:10.3762/bjnano.10.68

• ][31]. This work, however, used a different LDH platelet composition (Zn2Al) that is known to present some UV screening due to Zn2+ cations. However, hydrotalcite-type Mg2Al (as used in this work) has yet to be investigated. The temperature and frequency-dependent mechanical relaxation data for the

A carrier velocity model for electrical detection of gas molecules

• Ali Hosseingholi Pourasl,
• Sharifah Hafizah Syed Ariffin,
• Mohammad Taghi Ahmadi,
• Razali Ismail and
• Niayesh Gharaei

Beilstein J. Nanotechnol. 2019, 10, 644–653, doi:10.3762/bjnano.10.64

• configurations were considered. Several orientations of the C–O bond above the AGNR plane were tested. After a complete relaxation of the structure, the optimal configuration for the CO molecule above the AGNR was found, where the C–O bond was parallel to the substrate and the molecular distance from the AGNR

Enhancement in thermoelectric properties due to Ag nanoparticles incorporated in Bi₂Te₃ matrix

• Srashti Gupta,
• Dinesh Chandra Agarwal,
• Bathula Sivaiah,
• Sankarakumar Amrithpandian,
• Kandasami Asokan,
• Ajay Dhar,
• Binaya Kumar Panigrahi,
• Devesh Kumar Avasthi and
• Vinay Gupta

Beilstein J. Nanotechnol. 2019, 10, 634–643, doi:10.3762/bjnano.10.63

• electrons is caused by the existence of an electrostatic potential at the interface. The Seebeck coefficient depends on the energy derivative of the relaxation time at the Fermi energy. Thus the electron-energy filtering, in which high-energy electrons remain unaffected, strongly enhances Seebeck

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• relaxation times [31]. Nonetheless, this complicates time-domain measurements of ionic transport as the functional form of the relaxation must be fully captured in order to reliably extract the relevant parameters, namely τ* and β. With slow ionic relaxation times (longer than milliseconds) and typical

• operating (scanning) parameters (bandwidth of ca. 100 Hz) the PLL response will not affect the extracted values obtained from directly fitting the data. However, as the relaxation time approaches the response time of the PLL, the output signal will become a convolution of the PLL response function and the

• ionic relaxation. This makes any quantification of the transport properties challenging. To investigate the effect of τPLL on the ability to extract parameters from measured signals, a digitially synthesized voltage waveform varying in time as a stretched exponential (Equation 1, β = 0.7) was applied

Direct observation of the CVD growth of monolayer MoS₂ using in situ optical spectroscopy

• Claudia Beatriz López-Posadas,
• Yaxu Wei,
• Wanfu Shen,
• Daniel Kahr,
• Michael Hohage and
• Lidong Sun

Beilstein J. Nanotechnol. 2019, 10, 557–564, doi:10.3762/bjnano.10.57

• the interband transitions transpiring near the critical point of Γ, where the valance and conduction bands are nested [30]. The relaxation of the transitions A and B gives strong PL emission, which is plotted in Figure 1f. The strong PL emission corroborates the monolayer thickness of the MoS2 layer

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• of the permittivity. In particular, β-relaxation is affected by the addition of nanoparticles as well as the dissipation factor, which is even improved. A dielectric constant of 5 ± 1 with a dissipation factor of less than 0.045 in the range from 0.1 Hz to 1 MHz is obtained for a 2.7 µm thick NCPC

• relaxation of the C–Cl bond (β-relaxation) [34]. Compared to the pure parylene sample (O) all other samples present a higher dielectric constant over the whole frequency range. Many factors could explain this result: 1. An increase in polymer thickness sometimes leads to an increase in the dielectric

• parameter modifying the frequency trend of the β-relaxation is the dielectric strength Δε = ε’LF − ε’HF [62], where ε’LF is the low-frequency dielectric constant (measured at 0.1 Hz in our case) and ε’HF is the high-frequency dielectric constant (measured at 1 MHz in our case). Δε is associated to the

Intuitive human interface to a scanning tunnelling microscope: observation of parity oscillations for a single atomic chain

• Sumit Tewari,
• Jacob Bakermans,
• Christian Wagner,
• Federica Galli and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2019, 10, 337–348, doi:10.3762/bjnano.10.33

• temperature difference with the reference temperature T0 with an adjustable coupling to a heat bath: where τB is the temperature relaxation time, related to the strength of the coupling. The velocities of all atoms are rescaled at every timestep (Δt) with the same factor: A typical value for τB in condensed

• structural relaxation step in a system analogous to the one shown in Figure 3 and checked the difference in the final total energy of the relaxed state between our method and a conventional approach. We found that the error in final total energy induced by the cutoff radii and the lookup table is very small

• unwanted adsorbates that may be present in the UHV chamber, most likely hydrogen. In fact we have observed this jump to contact when approaching a Au adatom from the top in more than 80% of the times and we attribute it to the relaxation [42] of tip and surface atoms. Recent work [43][44], albeit not

Mechanism of silica–lysozyme composite formation unravelled by in situ fast SAXS

• Tomasz M. Stawski,
• Daniela B. van den Heuvel,
• Rogier Besselink,
• Dominique J. Tobler and
• Liane G. Benning

Beilstein J. Nanotechnol. 2019, 10, 182–197, doi:10.3762/bjnano.10.17

• of the protein molecules are considerably smaller than the native dimensions of lysozyme in any possible orientation. Hence, this suggests that initially the binding of silica NPs by lysozyme involves a severe deformation/unfolding of the protein molecules, followed in time by a relaxation and

• model to link the evolution in the measured structure factor to the lysozyme molecule, and we found that the aggregation processes involve severe deformation of the protein molecules, which is then followed by the relaxation towards the original dimensions. Appendix Derivation of Equation 17 The

Pull-off and friction forces of micropatterned elastomers on soft substrates: the effects of pattern length scale and stiffness

• Peter van Assenbergh,
• Marike Fokker,
• Julian Langowski,
• Jan van Esch,
• Marleen Kamperman and
• Dimitra Dodou

Beilstein J. Nanotechnol. 2019, 10, 79–94, doi:10.3762/bjnano.10.8

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

• Mateusz Mrukiewicz,
• Krystian Kowiorski,
• Paweł Perkowski,
• Rafał Mazur and
• Małgorzata Djas

Beilstein J. Nanotechnol. 2019, 10, 71–78, doi:10.3762/bjnano.10.7

• light (τ90–10). It was found that τON increases with the increase of the GO concentration. The effect can be attributed to the increase of the rotational viscosity γ. Figure 7b illustrates the τOFF dependence. The switch-off time is the time of the director relaxation after removing an electric signal

Hydrogen-induced plasticity in nanoporous palladium

• Markus Gößler,
• Eva-Maria Steyskal,
• Markus Stütz,
• Norbert Enzinger and
• Roland Würschum

Beilstein J. Nanotechnol. 2018, 9, 3013–3024, doi:10.3762/bjnano.9.280

• relaxation). When the PdHβ-phase vanished, the lattice constant of PdHα was reported to be higher than its value before initial absorption, indicating an irreversible effect of the hydrogen treatment on the lattice [38]. It is important to note that also during absorption a decrease in lattice constant for

• the process of lattice-constant relaxation in the α-phase, while the fraction of PdHβ is reduced. Region (e) corresponds to the desorption from PdHα, which is the predominant phase at this point, until the sample is completely dehydrogenated. The same strain overshoot was monitored during desorption

• sample contracts as expected with a strain rate approximately proportional to the unloading current. The relaxation of the strained α-phase appears without an externally applied potential or current (black after unloading in red), resulting in a similar overshooting effect. As indicated above, a possible

Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• complex processes, namely ionization (1 and 2), excitation (3) and relaxation (4) as well as dissociation in case of diatomic species (5) [75]: Thus controlled rf plasma treatment is a very interesting technique for the modification of surfaces as a number of different chemical species can be generated

Variation of the photoluminescence spectrum of InAs/GaAs heterostructures grown by ion-beam deposition

• Alexander S. Pashchenko,
• Leonid S. Lunin,
• Eleonora M. Danilina and
• Sergei N. Chebotarev

Beilstein J. Nanotechnol. 2018, 9, 2794–2801, doi:10.3762/bjnano.9.261

• intensity at 0 radians (θs = 33°) from the GaAs substrate, and low-intensity peaks with negative Δθ due to the strained GaAs1−xBix epitaxial lattice. That kind of peak splitting (with respect to the substrate) is usually observed in epitaxial layers with lattice relaxation. The Bi contents were calculated

• methods also show that the InAs/GaAs1−xBix heterosystem has a large lattice relaxation compared to that of InAs/GaAs. It is demonstrated that the surface diffusion of In increases during ion-beam deposition of InAs QDs on the GaAs1−xBix surface. a) Photoluminescence spectra of samples with vertically

Near-infrared light harvesting of upconverting NaYF₄:Yb³⁺/Er³⁺-based amorphous silicon solar cells investigated by an optical filter

• Daiming Liu,
• Qingkang Wang and
• Qing Wang

Beilstein J. Nanotechnol. 2018, 9, 2788–2793, doi:10.3762/bjnano.9.260

• in Figure 2c, under 980 nm excitation with a power of 60 mW, Yb3+ ions firstly capture the energy of the photons and then transfer it to neighboring Er3+ ions in a 4I11/2 → 4F7/2 transition. After non-radiative relaxation to lower energy levels, the excited electrons return to the ground level (4I15

Size-selected Fe₃O₄–Au hybrid nanoparticles for improved magnetism-based theranostics

• Maria V. Efremova,
• Yulia A. Nalench,
• Eirini Myrovali,
• Anastasiia S. Garanina,
• Ivan S. Grebennikov,
• Polina K. Gifer,
• Maxim A. Abakumov,
• Marina Spasova,
• Makis Angelakeris,
• Alexander G. Savchenko,
• Michael Farle,
• Natalia L. Klyachko,
• Alexander G. Majouga and
• Ulf Wiedwald

Beilstein J. Nanotechnol. 2018, 9, 2684–2699, doi:10.3762/bjnano.9.251

• light scattering data (Table S1, Supporting Information File 1). The ability of magnetite NPs to increase the T2-contrast in MRI arises from the creation of huge magnetic field gradients, accelerating the relaxation rate of water protons in the vicinity of the NPs [56]. The correlation of r2-relaxivity

• and the corresponding stray field are so large that water molecules experience a nearly constant magnetic field during their T2-relaxation. These NPs are then in the so-called static dephasing regime (SDR) [63], which determines the relaxivity limit, and the r2 value reaches a plateau. In the SDR, the

• in agarose in comparison with water solutions (Figure 5C), while for the smaller NPs, lower r2 values are observed. This splits the batches into two size regimes, namely SDR and MAR for the larger and smaller batches, respectively. According to these relaxation regimes, the NPs up to about 20–25 nm

High-temperature magnetism and microstructure of a semiconducting ferromagnetic (GaSb)_1−x(MnSb)_x alloy

• Leonid N. Oveshnikov,
• Elena I. Nekhaeva,
• Alexey V. Kochura,
• Alexander B. Davydov,
• Mikhail A. Shakhov,
• Sergey F. Marenkin,
• Oleg A. Novodvorskii,
• Alexander P. Kuzmenko,
• Alexander L. Vasiliev,
• Boris A. Aronzon and
• Erkki Lahderanta

Beilstein J. Nanotechnol. 2018, 9, 2457–2465, doi:10.3762/bjnano.9.230

• carriers their interaction have to be sufficiently strong. This implies that has to be a large amount of such inclusions with distances between them shorter than the carrier spin-relaxation length. However, the comparatively high carrier mobilities in the studied samples still leave some doubt on the

Influence of the thickness of an antiferromagnetic IrMn layer on the static and dynamic magnetization of weakly coupled CoFeB/IrMn/CoFeB trilayers

• Deepika Jhajhria,
• Dinesh K. Pandya and
• Sujeet Chaudhary

Beilstein J. Nanotechnol. 2018, 9, 2198–2208, doi:10.3762/bjnano.9.206

• -magnon propagation [15][16][17][18][19][20][21]. Besides spin transport, it is important to understand and tune the magnetic relaxation in multilayers from both fundamental physics and technological viewpoints. There are many applications that require low damping of gyromagnetic precession, e.g., in

• lowering the spin torque critical current switching density [22][23]. For various other applications a fast relaxation is favored, e.g., in magnetoresistive heads [24][25]. The FM/AF exchange coupling is one of the approaches to tune the magnetization relaxation by enhancing the field linewidth ΔH and

• displacing the resonance field Hr [26][27][28][29]. Spin transport and relaxation studies in FM/AF/FM trilayers are intriguing due to the presence of two interfaces shared between FM and AF. Also, little is known about how effective magnetic damping evolves when there is a weak interlayer exchange coupling

Dumbbell gold nanoparticle dimer antennas with advanced optical properties

• Janning F. Herrmann and
• Christiane Höppener

Beilstein J. Nanotechnol. 2018, 9, 2188–2197, doi:10.3762/bjnano.9.205

• enhancement due to the interaction of the molecule with the evanescent electromagnetic field of the antenna and 2.) quenching of the excited state, i.e., the relaxation of the excited state by means of radiationless energy transfer to the metallic interface of the AuNP. Since the spontaneous emission rate

Fabrication of photothermally active poly(vinyl alcohol) films with gold nanostars for antibacterial applications

• Mykola Borzenkov,
• Maria Moros,
• Claudia Tortiglione,
• Serena Bertoldi,
• Nicola Contessi,
• Silvia Faré,
• Angelo Taglietti,
• Agnese D’Agostino,
• Piersandro Pallavicini,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2018, 9, 2040–2048, doi:10.3762/bjnano.9.193

• materials that can coat surfaces and are capable of eradicating biofilms with remote physical activation. Even though gold nanoparticles are not intrinsically antibacterial, the thermal relaxation upon NIR light activation can be a major force of antibacterial action as it was shown for monolayers of GNSs

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• structure of bulk and nanoscale objects, illustrating the so-called “phonon bottleneck” phenomenon. The excitation relaxation time is enhanced when the spacing between the size-quantized energy levels ΔE is larger than the vibrational energy ħω. This mechanism is discussed for illustration purposes only

• . There are many other nonradiative relaxation channels in nanosystems that affect the excitation lifetimes. Reproduced with permission from [83], copyright 2010 American Institute of Physics. (d–i) Production of defects in graphene under ion irradiation as revealed by the analytical potential molecular

Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

• colloids” for more details). However, in more conventional nanomanipulation experiments such a transition could not yet be actively induced, most probably due to insufficient normal forces [50][76][84]. Nonetheless, this does not mean that interface-relaxation effects play no role even for relatively rigid

The inhibition effect of water on the purification of natural gas with nanoporous graphene membranes

• Krzysztof Nieszporek,
• Tomasz Pańczyk and
• Jolanta Nieszporek

Beilstein J. Nanotechnol. 2018, 9, 1906–1916, doi:10.3762/bjnano.9.182

• trajectories where the bond is broken at a later time t [24]. Because the probability that in a large system at equilibrium a particular donor–acceptor pair is hydrogen-bonded is small, the correlation function c(t) relaxes to zero and therefore k(t) describes the rate of relaxation to equilibrium. It is worth

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• , two tops of the Sn sites (T1 and T2), and two centres of the hexagonal sites (H1 and H2). The hydrogen is bounded to two S atoms and one Se atom at the T1 and H1 sites, whereas it is bounded to one S atom and two Se atoms at the T2 and H2 sites. After full relaxation, the T and H sites are not